BEARINGS

&

LUBRICATION

PRINCIPLES OF FRICTION

TYPES OF BEARINGS

S O L ID S P L IT H A L F T IL T IN G P A D

JO U R N A L B E A R IN G(R A D IA L L O A D )

G . C Y L IN D E R &R ID E R R IN G

G U ID E B E A R ING(B A C K & F O R T H )

M O T IO N

G . V E R T IC A L F A N

T H R U S T B E A R IN G / T IL T IN G P A D(A X IA L L O A D)

(A R E A C O N T A C T )

P L A IN B E A R ING

(P O IN T O R L IN E C O N T A C T )

R O L L IN G E L E M E NTO R

A N T I F R IC T IO N B E A R IN G

B E A R IN G

BEARING ARRANGEMENT

THRUST

RADIAL

BEARING ARRANGEMENT

THRUST

RADIAL

BEARING ARRANGEMENT

ANTIFRICTION BEARINGS

• BALL BEARINGS

•RADIAL BALL BEARING

•ANGULAR CONTACT BALL BEARING

• ROLLER BEARINGS

• CYLINDRICAL ROLLER BEARING

• TAPER ROLLER BEARING

• SPHERICAL ROLLER BEARING

• NEEDLE ROLLER BEARING

BEARING NOMENCLATURE

LOAD DIRECTION

BALL BEARINGS

ROLLER BEARINGS

NEEDLE ROLLER BEARINGS

BEARING LIFE

LOAD CARRYING SURFACES

BEARING DESIGNATION

BEARING DESIGNATION

BEARING FAILURE ANALYSIS

A SURVEY REVEALS :

• 9% FAILURE DUE TO FATIGUE.

• 27% FAILURES DUE TO IMPROPER MOUNTING & DISMOUNTING.

• 43% FAIL DUE TO IMPROPER LUBRICATION.

• 21% FAILURES DUE TO OTHER CAUSES.

OBJECTIVE:

• 100% FAILURES DUE TO NORMAL FATIGUE.

FRICTION BEARINGS

TILTING PAD BEARINGSLEEVE BEARINGS

WORKING PRINCIPLE

TILTING PAD RADIAL BEARING

TILTING PAD THRUST BEARING

LUBRICATION

WHY LUBRICATION??

• Formation of protective film to

Reduce friction Prevent corrosion Remove wear particles and debris Provide efficient cooling Reduce wear Shock absorption Overall life improvement

LUBRICATION THEORY

• Full film

• Static

• Hydrodynamic

• Elastohydrodynamic

• Application of pressure / load

• Depends upon speeds, loads, lubricant viscosity

• Boundary layer

• Layer separation not complete

• Results from insufficient lube, incorrect lube

GREASE Vs OIL

When greases?

Normal speed and temp conditions Simpler / cheaper installation Better adhesion Protection against impurities Less frequent application required

When Oils?

High Speed and temp Excellent cleaning and flushing characteristics Can be used in recirculative systems Can serve better in excessive dirt environment More stable than greases

LUBE OIL PROPERTIES

Viscosity Viscosity indexFlash point Pour pointOxidation stabilityDemulsibilityLoad carrying ability (EP)DetergencyTAN / TBN

TYPES OF LUBRICANTS

• Automotive oils Engine oils Gear oils Transmission oils Other oils (preservative oils etc)

• Industrial oils Turbine oils Hydraulic oils Gear oils Refrigeration compressor oils

• Greases• Synthetic oils

LUBE OIL SELECTION

OEM recommendationViscosity & VIBearing and lubrication typeOperating temperature

LUBE OIL MONITORING

Lube oil levelOil pressureOil inlet and outlet tempLube cooler inlet & outlet tempOil filter DPBearing temp

WDA Concept Every lubricated wear surface generates particles

There is a gradual build up of small particles in a normal system

When abnormal wear begins, there is no sharp instantaneous increase in the concentration of small particles present in the system

Large particles, however, reach a dynamic equilibrium in a normal system (filtration)

When abnormal wear begins, there is a dramatic increase in the concentration of large particles

Therefore, detection, measurement and analysis of these large wear particles can provide early and accurate information about the condition of the machine

WDA Methodology• Particle Size

• Composition

• Shape

• Concentration

WDA Trend Graph

• Lubricant Analysis– Monitoring of the lubricant

– Condition of the lubricant

– Viscosity, TAN, TBN, Water content, Insolubles

• Wear debris Analysis– Monitoring of wear particles

– Condition of the machine

– Quantity of wear particles in ppm

Oil analysis Vs WDA

WDA : Advantages and disadvantages

Advantages:

Provides early warning

Identifies lubricant contamination

Identifies specific failing components

Helps monitor component deterioration

Disadvantages:

Trending is necessary

Accuracy depends on sampling point, skill